Once you have a list of actions to mocap, the next thing to do is write down everything you’ll need know in order to perform them.

When you’re planning a mocap shoot, it’s really important you know everything you can about the actions you’re going to capture. From the character’s motivation to the size and shape of the prop they’re holding. Everyone will have questions about how the actions need to be performed and what you’ll need in order to perform them.

So, the more information you can give them, the more they’ll be able to help. The more they’re able to help, the more lifelike and believable your characters will feel, and ultimately, the smoother your project will run.

Performance Requirements

To start with, think about “WHY” your character is doing the action.

Understanding your character’s motivation is one of the most important parts of creating a believable performance. While “finding one’s motivation“‘ can sound a little arty, getting it right will really help your actors with their performance, which in turn will improve the belivability of your character.

Try to answer the who, what, why, and where of each action:

Who is performing the action?

• Which character is performing the action?
• How does this affect the action?

What are they doing?

• Have they done it before?
• What have they just done and what are they about to do?

Why are they doing it?

• What is the motivation or objective behind the action?
• What is the character thinking?

Where are they doing it?

• What effect do the surroundings have on the action?
• What effect does the environment have on your character?

Technical Requirements

Once you understand the “WHY” of the action, next you need to work out the “HOW”.

Knowing exactly how the action needs to be performed technically can save you a lot of time, pain and money later on. The less time you have to spend fixing technical issues, the more time you can spend animating your character.

Context

The first thing to think about is where you character is and what they’re in the middle of doing. For almost every action you capture, your character won’t have just appeared at that moment in time, they will usually be in the middle of doing something. Try to think about how what they’ve just done and what they’re going to do next will affect what they’re doing right now. How did they get here? What happened on the way? Where will they go next? What are they feeling emotionally and physically? If your character is “doing” rather than “moving”, it will make their actions much more believable.

Start & End Pose

Once you know where your character is and what they’re doing, you can work out how the actions starts and stops. The start and end poses are usually defined by the preceding and following scenes or actions. It is vital you know what pose or postion your character needs to start and end in, especially if the actions needs to blend into another action or match an existing shot. These could be staging or blocking notes: “Enter through door and walk to table“. Or technical notes: “Idle Base Pose To Combat Base Pose“.

Direction

Once you know where the character starts and ends, you can work out which directions they need to travel. Sometimes it could as simple as moving forwards in a straight line. Other actions may require more complicated changes in directions or movement through an environment. Again, these could be blocking notes: “CharacterA backs into corner“. Or technical notes: “Stand Turn 180º Counterclockwise To Run“

Distance

When you know which direction they’re going, you can work out how far they’ll need to go. This is usually determined by where the actions is happening or the technical requirements of the game mechanic or simulation. It could be a distance you need to measure, for example, the length of a step to the gap between to objects. You will also need to think about how the scale difference between your performer and your character effects this measurment if they are not the same proportions.

Duration

Once you know the distance they travel, you can work out how long they have to get there. There are a number of things that can determine the duration of an action: It might need to last a certain number of frames to “feel” responsive or avoid “feeling” repetitive; or it might need to match a shot or sequence length. Existing frame counts or timecodes are a good starting point or you can use a stopwatch to time yourself performing the action. Knowing the approximate duration of the action in seconds will also help estimate the cost of your mocap data later.

Response

Once you know the how long the action will last, you can work out when the action needs to happen. Some actions may need to be “triggered” instantly on a button press or simulation event, while others may need to occur on a specific frame, cue, or beat to synchronise with an existing event. The response time can also affect how the action “feels”: if it happens immediately, it will feel “fast and snappy” but if it takes a while, it will feel “slow and laggy“.

Pace/Speed/Tempo

Now you know when the actions needs to happen, you can work out how to pace it. The pace, speed or tempo of the action can vary depending how and where it will be used. You may need the tempo to be consistant for a walk cycle, but you may need to change the speed to create a slow and fast variation. Varying the pace or tempo of an action can also change the way it’s perceived by the audience: “Slow and thoughtful” or “Quick and efficient”.

Intensity/Skill

When you know what your character is doing, you can think about how well they can do it. The same type of action may need different levels of intensity or skill for different shots, game levels or characters. Decide what the different levels look like and most importantly, how they’re different from each other: “high energy screaming and waving” to “low energy slow clap”. “simple street brawler punch” to “trained multi-hit take down”. And then make a note of it (this is also a good way to create variations, which we’ll look at next)

Variation

The last thing you might need to think about is, how you can vary the actions. If you are planning to capture variations of an action, make sure you know exactly what those variations are and what they look like. Don’t be tempted to write “Idle_01”, “Idle_02”, or “var01”, “var02” and hope to invent something on the day. It can be difficult enough to come up with variations at the best of times, without all the added pressure of being on a shoot.

Props

Now you know how the character will be moving, you can make list everything they’ll need to use. Include everything the performer needs to picks up, puts down, takes out, or hold. Make sure you know the size, shape and weight of the prop based on the character’s size and strength in their world NOT your performer in this world. Also, remember to make a note of how the prop is held and which hand it’s in, and if you want to capture it – you’ll need this for estimating the cost later on.

Scenery

Once you have a list of props, you’ll need a list of anything else they interact with. If the performer has to interact with the scenery or environment in any way, you need to know the size, shape, weight and position of the objects (again, based on your character’s size, not the performer). This includes everything from a simple box to sit on to a complex set to move around in. The mocap volume is essentially a huge empty box. If the action needs anything more than a flat floor to stand on, you will need to bring it with you.

Association

The last thing to do is make a note of which which character or characters will be performing the action, and which shot, sequence or level it’s associated with. This will help remind you how the actions needs to be performed based on who’ is performing’s doing it and where they are. It will also help identify how often the action will be used, if it can be used in other situations, and if it needs to be removed or updated if something changes or gets dropped. And finally, you’ll need to know which character to map the mocap data to after the shoot.

How to Capture it

Now you know exactly what your performer will doing, your next job is to figure out how to capture them doing it.